The typical malaria spleen is the ague cake of malarial cachexia. Here we have a greatly enlarged spleen with a thickened capsule and firm consistence. This spleen may fill up one side of the abdomen.
Malta Fever.—The splenic enlargement in this disease usually corresponds about to that of typhoid fever. At times, however, the size may be so great as even to suggest kala-azar.
Relapsing Fever.—Splenic enlargement and tenderness are marked features in this disease, often being noted early in the course.
Blackwater Fever.—The spleen is painful and enlarged. The splenic enlargement in this disease and relapsing fever is important in differential diagnosis from yellow fever, a disease in which the spleen is unaffected.
The spleen may be enlarged in Japanese schistosomiasis as well as in rectal schistosomiasis.
Darling has recently noted that it may be difficult to differentiate the anaemia of malarial cachexia from that due to hookworm disease. As a matter of fact most authorities note a diminution in the size of the spleen in ancylostomiasis rather than an increase and splenic enlargement would certainly favor a diagnosis of malarial anaemia.
One point of distinction between spotted fever of the Rocky Mountains and typhus fever is that the spleen of the former disease is enlarged three or four times the normal, while that of typhus fever shows no increase in size. The palpable spleen of Rocky Mountain fever is firm instead of soft as with typhus fever.